* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #f97316;
    /* Orange */
    --primary-dark: #ea580c;
    /* Dark Orange */
    --primary-light: #fdba74;
    /* Light Orange */
    --success-color: #10b981;
    --error-color: #ef4444;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --bg-light: #f9fafb;
    --white: #ffffff;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: linear-gradient(135deg, #1e3a8a 0%, #f97316 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem 1rem;
    line-height: 1.6;
}

.container {
    width: 100%;
    max-width: 600px;
}

.registration-card {
    background: var(--white);
    border-radius: 20px;
    box-shadow: var(--shadow-xl);
    overflow: hidden;
    animation: slideUp 0.5s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.header {
    background: linear-gradient(135deg, #1e3a8a 0%, #f97316 100%);
    color: var(--white);
    padding: 2.5rem 2rem;
    text-align: center;
}

.header h1 {
    font-size: 1.875rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    letter-spacing: -0.025em;
    line-height: 1.3;
}

.subtitle {
    font-size: 1rem;
    opacity: 0.95;
    font-weight: 400;
    margin-bottom: 0.25rem;
}

.conference-date {
    font-size: 0.9375rem;
    opacity: 0.9;
    font-weight: 500;
    margin-top: 0.5rem;
}

.registration-form {
    padding: 2.5rem 2rem;
}

.form-group {
    margin-bottom: 1.75rem;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    letter-spacing: 0.025em;
}

.required {
    color: var(--error-color);
    margin-left: 2px;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    background-color: var(--white);
    color: var(--text-primary);
    transition: all 0.3s ease;
    font-family: inherit;
    outline: none;
}

.form-group input:focus,
.form-group select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group input:hover,
.form-group select:hover {
    border-color: var(--primary-light);
}

.form-group select {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%236b7280'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.75rem center;
    background-size: 1.25rem;
    padding-right: 2.5rem;
}

.helper-text {
    display: block;
    font-size: 0.875rem;
    color: var(--primary-color);
    margin-top: 0.5rem;
    font-weight: 500;
}

.info-notice {
    background: linear-gradient(135deg, #e0f2fe 0%, #dbeafe 100%);
    border-left: 4px solid var(--primary-color);
    padding: 1rem 1.25rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    margin-top: 0.5rem;
}

.info-notice strong {
    color: var(--text-primary);
    font-size: 0.9375rem;
    display: block;
    line-height: 1.5;
}

.submit-btn {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, #f97316 0%, #1e3a8a 100%);
    color: var(--white);
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 1rem;
    position: relative;
    overflow: hidden;
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.submit-btn:active {
    transform: translateY(0);
}

.submit-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
}

.spinner {
    display: inline-block;
    width: 14px;
    height: 14px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: var(--white);
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

.success-message {
    padding: 3rem 2rem;
    text-align: center;
    animation: slideUp 0.5s ease-out;
}

.success-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    font-weight: 700;
    box-shadow: var(--shadow-lg);
    animation: scaleIn 0.5s ease-out 0.2s backwards;
}

@keyframes scaleIn {
    from {
        transform: scale(0);
        opacity: 0;
    }

    to {
        transform: scale(1);
        opacity: 1;
    }
}

.success-message h2 {
    color: var(--text-primary);
    font-size: 1.75rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.reg-code {
    font-size: 1.125rem;
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
}

.reg-code strong {
    color: var(--primary-color);
    font-size: 1.5rem;
    font-weight: 700;
    display: block;
    margin-top: 0.5rem;
    letter-spacing: 0.1em;
}

.success-info {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 1.5rem;
}

.success-details {
    background: var(--bg-light);
    border-radius: 10px;
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    text-align: left;
}

.success-details p {
    margin: 0.5rem 0;
    color: var(--text-primary);
    font-size: 0.9375rem;
}

.success-details strong {
    color: var(--text-secondary);
    font-weight: 600;
    display: inline-block;
    min-width: 180px;
}

.success-details span {
    color: var(--text-primary);
    font-weight: 500;
}



/* Download buttons */
.download-btn {
    padding: 0.625rem 1.25rem;
    background: linear-gradient(135deg, #1e3a8a 0%, #f97316 100%);
    color: var(--white);
    border: none;
    border-radius: 8px;
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.download-btn:active {
    transform: translateY(0);
}

/* Input validation states */
.form-group input:invalid:not(:placeholder-shown),
.form-group select:invalid:not(:placeholder-shown) {
    border-color: var(--error-color);
}

.form-group input:valid:not(:placeholder-shown),
.form-group select:valid:not(:placeholder-shown) {
    border-color: var(--success-color);
}

/* Responsive Design */
@media (max-width: 640px) {
    body {
        padding: 1rem 0.5rem;
    }

    .header {
        padding: 2rem 1.5rem;
    }

    .header h1 {
        font-size: 1.5rem;
    }

    .registration-form {
        padding: 2rem 1.5rem;
    }

    .success-message {
        padding: 2.5rem 1.5rem;
    }

    .admin-section {
        padding: 1rem !important;
    }

    .admin-section h3 {
        font-size: 1rem !important;
    }
}

/* Floating WhatsApp Button */
.whatsapp-float {
    position: fixed;
    width: 60px;
    height: 60px;
    bottom: 40px;
    right: 40px;
    background-color: #25d366;
    color: #FFF;
    border-radius: 50px;
    text-align: center;
    font-size: 30px;
    box-shadow: 2px 2px 3px #999;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: all 0.3s ease;
}

.whatsapp-float:hover {
    transform: scale(1.1);
    background-color: #128C7E;
    box-shadow: 2px 4px 6px #666;
}

.whatsapp-icon {
    width: 35px;
    height: 35px;
    fill: currentColor;
}

.payment-instruction {
    font-weight: 800;
    /* Very bold */
    color: #8B0000;
    /* Dark red */
    font-size: 1.1rem;
}

.optional {
    font-weight: 800;
    /* Bold */
    font-size: 1.1rem;
    /* Increase size */
    color: #2563eb;
    /* Primary color to stand out, or keep inherit */
}

.back-link {
    display: inline-block;
    margin-bottom: 1rem;
    color: var(--white);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    opacity: 0.9;
    transition: all 0.2s;
}

.back-link:hover {
    opacity: 1;
    transform: translateX(-4px);
}